Mashing

Mashing is the process used to convert the starch in the cereals into sugar using the natural enzymes in the green malt. The mash is started by dropping green malt slurry (milled malt with water) into an empty mash tun.

The cooked cereal and water are then sprayed into the mash tun and mixed with the green malt slurry. During this time, a controlled volume of water is added so that the temperature of the mixture gradually rises. The mash is complete when the temperature reaches 63°C, which is the optimum temperature for the conversion of starch to sugar. Each mash consists of 30 tonnes of cereal and about 7 or 8 tonnes of green malt. The sugar solution produced by mashing is called ‘WORT’. It is filtered, cooled and pumped to the next stage which is fermentation.